2702results about "Generator control by field variation" patented technology

The throttle of an engine in an engine driven generator system operating subject to a wide and rapidly variable load, as in supplying current to a welder, is operated such that control signals are sent to a throttle actuator for adjusting the engine throttle position in response to load changes. The throttle actuator may be a solenoid pulling against a spring in accordance with the average current through the solenoid coil. In this embodiment, the processor causes pulse width modulated signals to be applied across the solenoid coil with throttle position changes being reflected in changes to the width of the pulses, such changes in the pulse width being delayed for at least the predetermined time since the last preceding adjustment to the throttle. Alternatively, the throttle actuator may be a stepper motor which is stepped by throttle position change signals from a processor which monitors engine speed and generator load to determine whether the throttle should be adjusted and, if so, in which direction and to what extent for optimum response.

In a multiple power source system of the present invention that has an inverter connected to a reactance, such as three-phase coils in a motor, a high voltage battery is connected with a low voltage battery via one transistor (Tr2) and one diode (D2) included in the inverter and one phase coil (U-phase coil) of the three-phase motor. The transistor Tr2 is turned on to make the electric current flow from the low voltage battery to the U-phase coil. The transistor Tr2 is subsequently turned off at a preset timing, so that the electric energy accumulated in the reactance, that is, the U-phase coil, flows through the diode D1 into the high voltage battery and thereby charges the high voltage battery. This arrangement enables the charging process from the low voltage battery to the high voltage battery without any complicated circuit structure for the voltage step-up. The three-phase motor may be unipolar driven with transistors connected to one side of the inverter. The arrangement of the present invention does not require any complicated structure, which undesirably increases the size of the multiple power source system, in order to ensure mutual supplement of the electric energy between electric systems having a large difference in voltage, for example, an electric system for driving a hybrid vehicle and an electric system for its control circuit.

A variable speed system for use in systems, such as, for example, wind turbines, is described. The system comprises a wound rotor induction generator, a torque controller and a proportional, integral derivative (PID) pitch controller. The torque controller controls generator torque using field oriented control, and the PID controller performs pitch regulation based on generator rotor speed.

A variable speed system for use in systems, such as, for example, wind turbines, is described. The system comprises a wound rotor induction generator, a torque controller and a proportional integral derivative (PID) pitch controller. The torque controller controls generator torque using field oriented control, and the PID controller performs pitch regulation based on generator rotor speed.

A touch switch apparatus for detecting the presence of an object such as a human appendage, the apparatus having a touch pad and a local control circuit connected to the touch pad and to a controlled device. The touch pad preferable includes a first electrode and a second electrode spaced from and surrounding the first electrode. The control circuit is preferably in integrated circuit form. A signal is provided to the touch pad to generate an electric field thereabout. Introduction of a stimulus near the touch pad disturbs the electric field. The control circuit detects the electric field disturbance in and generates a control signal in response.

A lightweight engine-driven generator set including a stator having at least first and second windings (preferably three-phase) and a rotor having a soft magnetic core and a plurality of high energy product permanent magnets, separated by consequence poles, disposed proximate the stator such that relative motion of the rotor and stator causes magnetic flux from the rotor to interact with and induce current in the stator windings. The first winding includes a predetermined number of turns corresponding to a first predetermined voltage output; and the second winding includes a predetermined number of turns corresponding to a second predetermined voltage output, the respective windings being grouped together as a unit and wound about the core such that the respective winding coils are wound in continuous close thermal contact with each other. The first winding generates a relatively high voltage, low amperage signal, and the second winding generates a relatively low voltage, high amperage signal; and a switch provides for selection of the desired output. Preferably the rotor is a hollow cylinder mounted on the engine shaft for rotation about the stator and such that the proper gap distance between rotor and stator is maintained during rotation of the rotor without bearings external to the engine. The low voltage, high amperage winding (or winding group) may be tapped to provide a selectable voltage output. Suitable rectifiers and inverters may be provided to effect selective DC and AC output signals.

The present invention relates to variable speed constant frequency (VSCF) devices and methods for maximizing engine generator efficiency. In one embodiment, a VSCF device may include at least two paths for conducting power to the load. One path, a line inductor path, may advantageously incur minimal power loss when the engine generator is supplying rated power to a load. A second path, a VSCF path, may be used to ensure that the frequency of the power is maintained at a substantially constant frequency under various load conditions. Another embodiment of the invention describes a process for determining optimal engine generator speed for a particular load. Because engine speed can be varied using any VSCF device, this process determines a speed that minimizes fuel consumption, emissions, and noise pollution for a given load.

A starter-generator (ISG) is mechanically connected to an internal combustion engine (BKM), comprises a bi-directional AC / DC converter (1), and can be connected to an accumulator (B1) by means of a first switch (S1), and connected to a double layer capacitor (DLC) by means of a second switch (S2). The accumulator (B1) is either connected to the double layer capacitor (DLC) by means of a control circuit (PWM), or the accumulator (B1) and the double layer capacitor (DLC) are connected to a bidirectional DC / DC converter (3) and to a second accumulator (B2) by means of a third switch (S3) and a fourth switch (S4).

A control system that can accommodate the wide variations in the output of a generator, such as a permanent magnet alternator, while providing an output with relatively uniform phase ripple. The control system includes a zero crossing detector and variable ramp generator for generating control signals to a switching rectifier to generate a regulated DC signal.

A system for controlling torque ripple in a permanent magnet synchronous machine includes a power converter configured to be coupled to the permanent magnet synchronous machine and to receive converter control signals and a system controller coupled to the power converter. The system controller includes a fundamental current controller configured for providing fundamental voltage commands, a harmonic current controller configured for using harmonic current commands, current feedback signals from the permanent magnet machine, and fundamental current commands in combination with positive and negative sequence regulators to obtain harmonic voltage commands, and summation elements configured for adding the fundamental voltage commands and the harmonic voltage commands to obtain the converter control signals.

An apparatus and related method generate electrical power in a tubular housing, such as a drill collar, disposed in a borehole when drilling fluid flows through the tubular housing. The apparatus includes a stator adapted for being secured within the tubular housing against rotation relative to the tubular housing, a tubular rotor rotatably carried about the stator, and an impeller peripherally affixed to the rotor. The stator has an array of conductive windings therein, and is preferably an alternator stator. The rotor has an array of magnets therein, and is preferably an alternator rotor. Accordingly, drilling fluid flowing through the tubular housing when the apparatus is disposed therein engages the impeller and induces rotation of the rotor about the stator to generate electrical power.

The present invention relates to a method and to a device for adapting the alternating current generated by a generator (1) and the alternating voltage generated by a generator (1) to a grid (8), whereby the generator (1) has at least one excitation coil (2). The power fed into the grid (8) can be flexibly adapted while entailing low switching losses in that a static frequency converter (9) is employed for the adaptation between the generator (1) and the grid (8), and in that, in order to control the power fed into the grid (8), means (3) are provided with which, on the one hand, the strength of the excitation field generated by the at least one excitation coil (2) is regulated and, on the other hand, the phase angle between the frequency converter voltage and the generator or grid voltage is appropriately controlled.

A wave energy converter has a shell, a pendulum pivotally positioned in the shell, a magnet thereon, a variable inductor positioned in the shell, a pendulum adjustor for changing a center of gravity of the pendulum, a motion sensor positioned in the shell, a position sensor connected to the pendulum, a rotation sensor connected to the pendulum, and a controller connected to the motion sensor and the position sensor and the rotation sensor. The pendulum has a magnet thereon. The magnet of the pendulum oscillates adjacent the variable inductor. The variable inductor can adjust the inductive capacity.

A control apparatus for a vehicle generator includes a switch, a regulator, a fault condition detector, and a PWM signal generator. The switch is selectively turned on and off so as to intermittently excite the generator. The regulator controls on / off operation of the switch so as to bring an output of the generator into agreement with a target value. The fault condition detector detects a fault condition of the generator. The PWM signal generator generates and outputs a PWM signal that has a duty determined as a function of a duty of the on / off operation of the switch and a frequency determined based on if the fault condition of the generator is detected by the fault condition detector. Consequently, the control apparatus can inform an external control apparatus of the duty of the on / off operation of the switch and the fault condition of the generator with the single PWM signal.

The invention is a control system that, among other things, controls a permanent magnet alternator and provides relatively accurate voltage regulation. The control system may include one or more of the following: (1) a rectification system to rectify and regulate the output voltage of an alternator, (2) a rectifier / limiter used as an electrical power source to a boost type regulator, (3) a multimode rectifier / limiter, (4) a DC to AC inverter bridge, and (5) power switches employed in the system to minimize the switching energy that would otherwise be dissipated in the power switches as heat.

An alternator system having an alternating current (ac) voltage source includes a switched-mode rectifier (SMR) coupled to the ac voltage source and having an output port coupled to an output of the alternator system, and a controller coupled to said switched-mode rectifier so as to provide a controlled pulse sequence synchronized with an angular rotor position of the (ac) voltage source to activate and deactivate the switched-mode rectifier. The controller further includes a PWM generator having a first input to receive a total duty ratio signal synchronized with an angular rotor position of the (ac) voltage source. The switched mode rectifiers are controlled to increase power output levels at lower speeds near idle. The controller combines improved idle speed power output levels with load matching improvements from PWM control for more efficient operation when compared to circuits using conventional control or PWM load matching control alone.

A vehicle generator control system detects a time point at which an electrical load is to be disconnected from the generator output, with the detection being achieved prior to that disconnection time point, and initiates a lowering of the generated current of the generator by an amount equal to the load current of that electrical load. The generated current of the generator is thereby reduced, by the time of the disconnection, to a value whereby substantially no voltage spike is produced in the generator output voltage.

The invention discloses a switch magnetic resistance generator system capable of realizing rapid excitation / demagnetization. The system comprises a switch magnetic resistance motor body, a prime mover, a position sensor, a power converter, a DC power supply and a controller, wherein the power converter is a four-level power converter. By adopting the four-level power converter, at an excitation stage, in an angle position control mode, the exciter current of a phase winding is increased, and the energy storage of a magnetic field is increased so that the output power of an overall power generation system is improved and it is easier for the power generation system to reach a rated power; in an current chopping control mode, the excitation time is reduced, rapid excitation is realized, and the time of a generating stage is increased so that the generating capacity of a motor is enhanced and the output power of the system is increased; and at the generating system, when two voltage sources are utilized, rapid demagnetization can be realized.

Disclosed is a controller of a grid coupled type doubly-fed induction generator having a multi-level converter topology, which can control the doubly-fed induction generator having a high voltage specification and can perform a fault ride-through function, an anti-islanding function and a grid voltage synchronization function required for a dispersed power generation facility. The controller makes a H-bridge multi-level converter generate a three-phase voltage waveform resulted from the structure that single-phase converters each being composed of a 2-leg IGBT are stacked in a serial manner, and controls a rotor current so as to make the rotor coil of the doubly-fed induction generator in charge of a slip power only. The boost converter is composed of a 3-leg IGBT and a boost inductor generating a direct current voltage of its source required for the H-bridge multi-level converter.

The invention discloses a starting power generation system for an electric automobile, which comprises a double salient pole starting power generator, a starting power generation controller and controller working power; the starting power generation controller comprises a bidirectional power conversion circuit, an exciting current detection unit, an output current detection unit, an output voltage detection unit, a position rotation speed detection unit, an armature current detection unit, an exciting main circuit and a digital signal processor, wherein the exciting main circuit includes an exciting relay, a rectification filter unit and a chopper circuit which are connected in series in turn; and the digital signal processor is connected with the exciting current detection unit, the output current detection unit, the output voltage detection unit, the armature current detection unit, the position rotation speed detection unit, and the control ends of the bidirectional power conversion circuit, the exciting relay and the rectification filter unit by signals respectively. The invention also discloses an electric automobile and a control method thereof. Compared with the prior art, the starting power generation system is simple in structure, low in cost and flexible to control.

An adaptive, sensorless position sensing apparatus (250) derives rotor position of a synchronous machine (200). The apparatus (250) comprises a first rotor position deriving unit (300) for generating first rotor position values by applying a first sensorless rotor position calculation technique, which emulates a resolver; a second rotor position deriving unit (400) for generating second rotor position values by applying a second sensorless rotor position calculation technique; and a rotor position result output unit (450) for outputting rotor position results over a range of rotor speeds as a function of the first rotor position values, the second rotor position values, and rotor speed.

A variable speed power generator system, includes a primary power induction generator (12), a secondary control induction (14), each of the induction generators having a rotor (22, 24) mounted so as to be rotated by a common shaft (16) of a variable speed prime mover (20), an inverter (50) connected to the stator (15) of the secondary control induction generator, a controller (30) connected to the inverter controls the output of the inverter, output of the primary induction generator is connected to the grid (51), controller provides output signal to the inverter based on selected inputs to the controller so that the output of the primary induction generator matches the active and reactive power requirements of the grid. An induction machine which includes a rotor having laminations and insulated cage bars, the bars being electrically isolated from on another as well as electrically insulated from the laminations.

A rotating electrical machine includes a two-phase rotor having two non-rotating solenoid-wound rotor coil assemblies and two interleaved pole assemblies. Each pole assembly is magnetically coupled to its respective coil assembly and rotates together with the machine shaft. Each pole assembly has four or more elongated pole pieces, two of which couple with one pole of a coil assembly and two of which couple with the other pole of that coil assembly. An exciter circuit independently controls the power variables provided to the rotor with respect to the stator to provide a variable-speed, variable-frequency (VSVF) motor system or VSVF generator system. The exciter energizes the solenoid-wound rotor coils with biphase AC electrical excitation, to produce a radial, rotating magnetic field at the pole pieces.

A method to incorporate the steady-state model of the generalized power flow controller into a Newton-Raphson power flow algorithm is disclosed. The disclosed method adopts a flexible steady-state model of the generalized power flow controller, which can be applied to calculate the power flow solution of a power grid embedded with STATCOM, UPFC, GUPFC and the generalized power flow controller in a single framework. The disclosed method only incorporates the control variables of the shunt voltage sourced converter into the state vector of Newton-Raphson power flow algorithm. The increment of state variables due to incorporating the generalized power flow controller is less than the prior art. Further, the method can preserve the quadratic convergence characteristic of the Newton-Raphson power flow algorithm after embedding the generalized power flow controller into a power grid.

A system, method, and apparatus for stabilizing interactions between an electrical generator and a nonlinear load are described. One illustrative embodiment includes an impedance element that is coupled to an output of the generator and a power source coupled to the impedance element. The power source applies power to, or across, the impedance element so as to reduce energy loss that would ordinarily occur due to energy dissipation by way of the impedance element. In many variations, the power source operates within a defined bandwidth so that a stabilizing effect is achieved outside of this bandwidth.

A field-adjustable motor control system includes a motor, an inverter coupled to provide energization to the motor, a controller coupled to the inverter, and a field adjustment circuit that provides field adjustment signals to the controller. The controller provides signals to control the output of the inverter in response to received input control signals and field adjustment signals. The input control signals define the controller's operating state that corresponds to a desired system operating state. The field adjustment signals and input control signals define a desired output parameter of the inverter for an operating state. In certain embodiments, fail-safe circuitry is also provided that includes a relay receiving controller signals. The relay's input is coupled to a line power and to the inverter output. The relay's output is coupled to the motor. If the controller fails, the relay couples the line power to the motor.

An alternator system (50, 52) that, in one aspect, utilizes a Lundell style alternator that is augmented by power electronic switching components (62) in the output section. In one embodiment, some of these power switching embodiments employ a scaling of stator turns and wire size to achieve the superior performance at higher speeds. The alternator system provides significantly enhanced power capability above idle as compared with classical Lundell alternator systems using Lundell alternators of the same size that are designed with the same power capability at idle. In one preferred dual voltage embodiment, a power switch (semi-conductor) connects the alternator output directly to the low voltage load at low engine speeds and when the power switch is "opened" at higher speeds, the alternator's power is channeled to the higher voltage. In a 14-volt / 42-volt dual-voltage system, this arrangement provides triple the alternator's power capability at high speeds as compared to a conventional unenhanced capabilities of the altenator system of the present invention are accomplished without increasing the alternator size or required current capacity and without using high frequency semiconductor power modulation (106).